Conventionally, cutting works of steel, casts and so on have been conducted by using a tool formed of a sintered material. Since an edge of a tool is exposed to a high temperature environment during a cutting work, the tool is required to have oxidation resistance, in addition to the characteristics such as abrasion resistance and chipping resistance. As sintered bodies for which such characteristics are expected, sintered bodies formed of Ti, Al, and N are known.
For example, Japanese Patent Laying-Open No. 05-078107 (PTD 1) discloses producing a sintered material formed of Ti0.5Al0.5N by making a powder formed of Ti0.5Al0.5N by using a mechanical alloying (MA) method, and sintering the powder. Japanese Patent Laying-Open No. 10-182233 (PTD 2) discloses producing a titanium aluminum nitride group sintered material by making a powder formed of Ti1-xAlxN (x=0.05 to 0.70) by a physical vapor-phase deposition (PVD) method, and sintering the powder. Japanese Patent Laying-Open No. 2007-131493 (PTD 3) discloses producing an Al-added TiN bulk body by making a mixture formed of Ti, Al, and N by a self-propagating high-temperature synthesis (SHS) method, and sintering the mixture.